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In this study, systematic development of a portable sensor for the rapid detection of Escherichia coli (E. coli) and Exiguobacterium aurantiacum (E. aurantiacum) was reported. A conductive glass was utilized as a substrate and developed the electrode patterns on it. Trisodium citrate (TSC) and chitosan-stabilized gold nanoparticles (AuNPs) (CHI-AuNP-TSC) and chitosan-stabilized AuNPs (CHI-AuNP) were synthesized and utilized as a sensing interface. The morphology, crystallinity, optical properties, chemical structures, and surface properties of immobilized AuNPs on the sensing electrodes were investigated. The sensing performance of the fabricated sensor was evaluated by using an electrochemical method to observe the current changes in cyclic voltammetric responses. The CHI-AuNP-TSC electrode has higher sensitivity toward E. coli than CHI-AuNP with a limit of detection (LOD) of 1.07 CFU/mL. TSC in the AuNPs synthesis process played a vital role in the particle size, the interparticle spacing, the sensor’s effective surface area, and the presence of CHI around AuNPs, thus enhancing the sensing performance. Moreover, post-analysis of the fabricated sensor surface exhibited the sensor stability and the interaction between bacteria and the sensor surface. The sensing results showed a promising potential for rapid detection using a portable sensor for various water and food-borne pathogenic diseases.

This paper documents the synthesis of magnetic carbon gels by encapsulating iron nanoparticles in porous carbon gel matrix and studying its application in dye adsorption and catalytic reduction reaction. The effects of magnetic nanoparticles under the purview of this study were investigated using X-ray diffraction, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer, Emmett and Teller (BET) surface area, Barrett–Joyner–Halenda (BJH) pore size distribution analysis, Raman spectroscopy and vibrating sample magnetometer. The adsorption capability of the magnetic gels in removing methylene blue dye pollutant from water was examined using different initial dye concentration (10–30 mg/L). The effect of pH, adsorbent dosage on adsorption and the kinetics, equilibrium and thermodynamics of the adsorption were investigated in detail. Spontaneous and favourable nature of the adsorption was confirmed with a maximum adsorption capacity of 67.75 mg/g. In addition, the catalytic properties of the gels were also probed using the model catalytic conversion of p-nitrophenol to p-aminophenol with NaBH4. The magnetic gels showed excellent activity towards the catalytic reduction of 60 ppm p-nitrophenol with a rate constant of 0.299 min−1, that is comparable with several previously reported catalysts. The response of the gel to external magnetic field made the catalyst easily recoverable. The immobilization of Fe nanoparticles in the graphitic carbon matrix prevented the aggregation as well as oxidation problem making it reusable without any significant loss in its catalytic activity.

CuZn-based catalysts are active in production of hydrogen by methanol steam reforming. However, there is a need to have further insight on their physico-chemical properties to improve selectivity to hydrogen. Therefore, a series of CuZn/MCM-41 catalysts was synthesized by four different routes; one pot hydrothermal synthesis (OPMCM), co-impregnation (COMCM), serial impregnation (SRMCM) and copper impregnated on Zn-MCM-41 (ZNMCM). Samples of catalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS), inductively coupled plasma (ICP) emission spectrometry, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). XRD revealed disruption in the ordered pore network typical in MCM-41 for all catalysts synthesized and also showed that the one pot synthesis catalyst had wide spread dispersion of Cu and Zn. SEM micrographs captured irregularly shaped particles of different sizes. While XPS showed that different Cu and Zn species were formed within the catalyst matrix. XPS also confirmed that there was wide spread dispersion and interaction of Cu and Zn with MCM-41 matrix in the OPMCM catalyst. COMCM and OPMCM demonstrated the highest activity with 88 and 65% methanol conversion with corresponding H2 selectivity of 91 and 86% respectively. They are better than SRMCM and ZNMCM which had average H2 selectivity of 19% and 31% respectively. CO selectivity was less than 1.8% for the COMCM and OPMCM catalysts. While SRMCM and ZNMCM had CO selectivity's as high as 8.9% and 7.2% respectively. The data generated shows that catalytic activity is largely affected by the nature of Cu species within the catalyst matrix.

Herein, we utilized waste triglycerides “cooking oil” as an abundant source for biodiesel (methyl esters) production via transesterification over a novel synthesized heterogeneous catalyst (Zn-MgO-ZrO2). The catalyst was prepared by the co-precipitation technique and analyzed by using X-ray diffraction, Scanning Electron Microscope, temperature desorption analysis and surface analysis to better understand the surface chemistry of the catalyst. Moreover, the biodiesel production process through transesterification by using Zn-MgO-ZrO2 was optimized. The optimal biodiesel yield was 92.3 wt% when the optimal set of process variables were at a temperature of 80 °C, molar ratio 12 (methanol and oil), time 4 h and catalyst amount was 4 wt%. The synthesized heterogeneous catalyst is reusable with almost equal efficiency as for the fresh catalyst. Different techniques also examined the quality of produced biodiesel according to the standard procedures defined by the American Society for Testing and Materials (ASTM) and European Union (EU) Standards.

Crude oil spillage has caused untold hardships to many communities. Cheap and effective treatment of these oil spills remains a challenge to environmentalists. The use of plant sorbent materials fo...

The kinematic viscosity of three kinds of nanofluids namely Al2O3/water, TiO2/water, and graphene/water was measured at different temperatures. Concentration of the metallic oxide nanoparticles in ...

Prunus Armeniaca seed (PAS) oil was utilised as a waste biomass feedstock for biodiesel production via a novel catalytic system (SrO–La2O3) based on different stoichiometric ratios. The catalysts have been characterised and followed by a parametric analysis to optimise catalyst results. The catalyst with a stoichiometric ratio of Sr: La-8 (Sr–La–C) using parametric analysis showed an optimum yield of methyl esters is 97.28% at 65 °C, reaction time 75 min, catalyst loading 3 wt% and methanol to oil molar ratio of 9. The optimum catalyst was tested using various oil feedstocks such as waste cooking oil, sunflower oil, PAS oil, date seed oil and animal fat. The life cycle assessment was performed to evaluate the environmental impacts of biodiesel production utilising waste PAS, considering 1000 kg of biodiesel produced as 1 functional unit. The recorded results showed the cumulative abiotic depletion of fossil resources over the entire biodiesel production process as 22,920 MJ, global warming potential as 1150 kg CO2 equivalent, acidification potential as 4.89 kg SO2 equivalent and eutrophication potential as 0.2 kg PO43− equivalent for 1 tonne (1000 kg) of biodiesel produced. Furthermore, the energy ratio (measured as output energy divided by input energy) for the entire production process was 1.97. These results demonstrated that biodiesel obtained from the valorisation of waste PAS provides a suitable alternative to fossil fuels.

Biodiesel is regarded as an environmentally friendly alternative fuel. The current research synthesises novel heterogeneous catalysts derived from waste (lab glassware and eggshells) and utilised for biodiesel production. Beef fat, abundantly available worldwide, is used as an oil feedstock and then converted into biodiesel, an environmentally friendly fuel. The synthesised catalyst consists of precursor silica dioxide (treated waste glassware) and calcium oxide (calcined from eggshells) that have been modified by impregnating cerium oxide to increase activity. The catalyst is characterised to ensure its suitability for the reaction to produce methyl esters (biodiesel) from animal fat, and biodiesel production is then tested. Characterisation revealed the suitability of the catalyst for the intended application, followed by a comprehensive parametric study to optimise the reaction conditions, including process temperature, time, methanol to oil molar ratio, and catalyst loading. According to the parametric study, the optimal conditions are as follows; process temperature (70 °C), time (100 min.), methanol to oil molar ratio (11) and catalyst loading (3 wt%), where the optimum biodiesel yield was 95.29 wt%. Furthermore, the produced biodiesel is then characterised to report its fuel properties and compared to standards (ASTM6751 & EN14214) which revealed its suitability as a potential alternative fuel. The reusability of the catalyst is also determined. The results indicated that it could be reused up to five times without a noticeable decrease in its reactivity. Based on the results, it can be concluded that synthesised catalysts from such waste materials are a viable option for commercial biodiesel production.

This study reports the synthesis of dual-functional heterogeneous catalyst for valorizing the plant-based oils to produce biodiesel as a cleaner fuel to conserve the environment and meet the current energy demand. Pristine carbon as a support for the catalyst is produced from waste date seeds powder before oil extraction and modified with alkaline earth metal oxides to utilize it for transesterification to produce biodiesel. The synthesized catalyst before usage is characterized by several techniques which include XRD, SEM, EDS, BET and TPD. The catalyst characterization revealed its suitability for transesterification reaction and the process is optimized while the synthesized catalyst is used for the reaction. The optimized yield of biodiesel is 94.27 wt% when the set parameters of a temperature of 65 °C, time 90 min, methanol to oil molar ratio of 15 and catalyst loading of 4 wt%. To commercialize the catalyst, the efficiency was evaluated using oils from different sources to produce biodiesel. The kinetic study revealed that while using the synthesized heterogeneous catalyst for transesterification of non-edible oil to produce biodiesel it was not an energy-intensive process. Further on, the fuel properties were measured and compared to American ASTM and European EN standards which ensured that the produced biodiesel is of potential and that it can be commercialized. Thus, the study gave an overall complete scenario from an economical catalyst to efficient fuel production which can be advantageous in the society.

A thin layer of gold nanoparticles (AuNPs) was deposited on glass substrates followed by subsequent deposition of silver nanoparticles (AgNPs) on it. Both AuNPs and AgNPs layers were fabricated by DC magnetron sputtering with inert gas condensation technique. The effect of initial thin layer of AuNPs have on the transformation of AgNPs surface structure by post annealing at 500 °C and 600 °C in air was investigated. The influence of post annealing temperature on the surface morphology was studied by atomic force microscopy and post annealing at 500 °C reduce the size of AgNPs along with the formation of some AgNPs inside the glass matrix. At 600 °C, aggregation of AuNPs on the surface was observed and increased in the number of AgNPs that diffused into the glass matrix. X-ray photoelectron spectroscopy was employed to study the surface composition and chemical states. The temperature dependence of Ag diffusion into the glass matrix was characterised and observed by UV–visible absorption spectroscopy and cross sectional transmission electron microscopy. Furthermore, ultraviolet photoelectron spectroscopy revealed a new shoulder related to Au 6 s hybridized with Au 5d and Ag 4d bands in the 1–4 eV regions, which affirmed the metallic character of AgNPs/AuNPs/glass system at higher annealing temperature. By introducing AuNPs on glass prior to AgNPs deposition, novel properties such as limited Ag ion diffusion and evaporation were found and problems previously encountered in AgNPs/glass system were avoided. The proposed AgNPs/AuNPs/glass system can be useful in plasmonic applications such as chroma filters and photonic devices.

Hydrogen production from methanol rather than the traditional source, methane, is considered to be advantageous in ease of transportation and storage. However, the current copper-based catalysts ut ...

A catalytic surface was fabricated by incorporation of electrochemically reduced graphene oxide (rGO) on poly(2,4,6-triaminopyrimidine) (PTAP) film modified glassy carbon electrode. The surface materials of the constructed electrode (rGO.PTAP/GCE) were characterized by means of electrochemical and surface scanning techniques including Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS) and X-ray Photoelectrons Spectroscopy (XPS). Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) were carried out to identify the preparation of the graphene oxide (GO). The heterogeneous rate constant (ks = 0.149 cm s−1) of the fabricated sensor was evaluated by Nicholson method. The synergistic effect of surface materials promotes the catalytic efficiency of the developed sensor for the detection of ephedrine (EPH) in pharmaceutical samples where the detection limit (DL3σ) of EPH was 1.8 μM (297 ppb). The diffusion coefficient of ephedrine (2.55 × 10−5 cm2·s−1) was also evaluated using theoretical electrochemical approach. The analytical performance of the sensor was successfully applied for real drug sample with acceptable analytical recovery percentage.

In this paper, activated carbon (AC) in the form of single and double threads is used for the first time as a pH sensor because of its intrinsic properties (high porosity, and conductivity). To determine its applicability as a pH sensor, this study characterizes the morphological features and measures the pH sensing characteristics of the AC threads. The pH sensing characteristics (sensitivity and hysteresis) of both single and double thread are: 19.66 mV/pH; 60.4 mV and 11.3 mV/pH; 144.6 mV, respectively. The AC single-thread exhibits a higher sensitivity for pH range of 2–12 with excellent linearity of 98.2%, and the lower hysteresis for pH (7-4-7-10-7) cycle. These values of pH sensitivity and hysteresis for AC single-thread make it a good EGFET candidate for use as a pH sensor. The high porosity and conductivity of the AC sensor explains its high pH sensing performance. Given the dependence of pH sensitivity on the ion-exchange between available [H+] in the electrolyte and the carbon ions available in the surface of the thread.

Characteristics of sugar crystals are important for developing set-syrup due to their contribution to the desired mouth feel when consumed. Two types of set-syrup (i.e. seeds with and without) were developed by storing the syrup at −20, 4 and 15 °C. The melting temperatures (onset and peak), and enthalpy of set-syrup without seeds (SN) were 30.2 °C, 74.6 °C and 42.2 kJ/kg respectively. In the case of SN, enthalpy decreased with the decrease of crystallization temperature (P 0.05). Polarized Light Microscopy (PLM) images showed that finer crystals were formed in the cases of set-syrups (i.e. SN and SW) as the storage temperature was decreased. X-ray diffraction (XRD) analysis showed the formation of different polymorphic sugar crystals. Crystallization temperatures at 4 and −20 °C can be used to produce finer crystals with varied polymorphic characteristics.

Doped magnetite (SnxFe3-2/3xO4) nanoparticles (NPs) (12–50 nm) with different amount of Sn2+ ions (x) were synthesized using co-precipitation method. Sn2+ doping reduces the anticipated oxidation of Fe3O4 NPs to maghemite (γ-Fe2O3), making them attractive in several magnetic applications. Detailed characterizations during heating–cooling cycles revealed the possibility of tuning the unusual observed magnetization dipping temperature/amplitude, irreversibility, and Curie point of these NPs. We attribute this dip to the chemical reduction of γ-Fe2O3 at the NPs surfaces. Along with an increase in the dipping temperature, we found that doping with Sn2+ reduces the dipping amplitude, until it approximately disappears when x = 0.150. Based on the core-shell structure of these NPs, a phenomenological expression that combines both modified Bloch law (M = M0[1 − γ(T/TC)]β) and a modified Curie–Weiss law (M = − α[1/(T − TC)δ]) is developed in order to explain the observed M-T behavior at different applied external magnetic fields and for different Sn2+ concentrations. By applying high enough magnetic field, the value of the parameters γ and δ ≈ 1 which are the same in modified Bloch and Curie–Weiss laws. They do not change with the magnetic field and depend only on the material structure and size. The power β for high magnetic field was 2.6 which is as expected for this size of nanoparticles with the core dominated magnetization. However, the β value fluctuates between 3 and 10 for small magnetic fields indicating an extra magnetic contribution from the shell structure presented by Curie–Weiss term. The parameter (α) has a very small value and it turns to negative values for high magnetic fields.

The current study describes the fabrication of chitosan‑zinc oxide nanorods composite (CHT/ZnO) on fiberglass panels (support substrate). ZnO nanorods (NRs) with size ranging from 20 to 100 nm and some microrods with an approximate size of 0.5–1 μm were grown on fiberglass panels. CHT 1%/ZnO composite had ZnO NRs incorporated into chitosan (CHT) coating while ZnO NRs were not visible in the CHT 2%/ZnO NRs composite. XRD and FTIR results showed the presence of the ZnO and chitosan. The water contact angle decreased from 80° ± 2° (control) to 65° ± 2° for CHT 1%/ZnO NRs and 42 ± 2° for CHT 2%/ZnO NRs composite coatings. The antimicrobial activities of the coated fiberglass panels were investigated using biofilm-forming bacteria Bacillus subtilis and Escherichia coli under both light and dark conditions. CHT/ZnO composite coated fiberglass panels showed the strongest antimicrobial activity compared to chitosan, ZnO NRs coatings, and Zn-based antifouling paint in the experiments with B. subtilis and E. coli under light conditions. The highest antifouling activity was observed for CHT 2%/ZnO composites. CHT/ZnO composites can be good alternatives to the toxic antifouling paints.

The application of highly active nano catalysts in advanced oxidation processes (AOPs) improves the production of non-selective hydroxyl radicals and co-oxidants for complete remediation of polluted water. This study focused on the synthesis and characterisation of a highly active visible light C&ndash, N-co-doped TiO2 nano catalyst that we prepared via the sol-gel method and pyrolysed at 350 &deg, C for 105 min in an inert atmosphere to prevent combustion of carbon moieties. Then we prolonged the pyrolysis holding time to 120 and 135 min and studied the effect of these changes on the crystal structure, particle size and morphology, electronic properties and photocatalytic performance. The physico-chemical characterisation proved that alteration of pyrolysis holding time allows control of the amount of carbon in the TiO2 catalyst causing variations in the band gap, particle size and morphology and induced changes in electronic properties. The C&ndash, N&ndash, TiO2 nano composites were active under both visible and UV light. Their improved activity was ascribed to a low electron&ndash, hole pair recombination rate that enhanced the generation of OH. and related oxidants for total deactivation of O.II dye. This study shows that subtle differences in catalyst preparation conditions affect its physico-chemical properties and catalytic efficiency under solar and UV light.

Advanced oxidation technologies (AOTs) focusing on nonthermal plasma induced by dielectric barrier discharge are adequate sources of diverse reactive oxygen species (ROS) beneficial for water and wastewater treatment. In this study, indigo, peroxytitanyl sulphate and terephthalic acid methods were used to approximate the concentrations of O3, H2O2 and OH produced in a double cylindrical dielectric barrier discharge (DCDBD) plasma configuration. The effect of pH and scavengers as well as the amount of chemical probes on the generation of oxidants was investigated. The efficiency of the DCDBD reactor was further evaluated using methylene blue (MB) as model pollutant. The results demonstrated that the formation of oxidants O3, H2O2 and OH in the DCDBD reactor was pH-dependent. Furthermore, the presence of scavengers such as phosphates, bicarbonates and carbonates in the solution diminished the amount of OH in the system and hence could impact upon the degree of detoxification of targeted pollutants during water and wastewater treatment. The MB simulated dye was totally decomposed into H2O, dissolved CO2 and simpler aqueous entities. Herein the DCDBD design is an adequate AOT that can be used worldwide for effective decontamination of water and wastewater.

Special and advanced techniques at drilling and production operations are used to drill and produce hydrocarbons from different eccentric reservoirs such as deep-water reservoirs, shale gas, and shale oil necessitates. However, these advanced techniques are considered to be costly and affecting the environment. Therefore, nanotechnology has been implemented in the drilling fluids to improve the rheological properties, hydrogen concentration, and filtration rate. This study is, therefore, aimed at evaluating the properties of zinc oxide nanoparticles and their previous implementation in drilling fluids, examining the rheological properties of water base mud from atmospheric temperature to downhole condition (90 °C). The experiment was designed to investigate the effect of nanoparticles concentration and temperature variation on the rheological properties of water-based mud using response surface methodology. A rotational viscometer was used to measure viscosity, yield point and gel strength. Moreover, a Consistometer was used to heat the fluid sample to different temperatures reaching up to downhole condition (90 °C). It was observed experimentally that addition of zinc oxide nanoparticles impressively improved the rheological properties of water-base mud by 50% for viscosity and gel strength, and 80% for yield point. It also allowed them to maintain their quality at all temperatures. Furthermore, addition of higher concentrations of zinc oxide nanoparticles of more than 1 wt% (6 g) at low temperatures (below 40 °C) gave the highest and most effective results of the rheological properties.

Activated carbon clothes (ACCs) were modified by in situ deposition of silica nanoparticles (SiO2 NPs) to enhance the dielectric property of ACC surface and used as electrodes in the capacitive deionization (CDI) system. Four different concentrations of tetraethyl orthosilicate precursors were used as silica source and the effect of concentration on the CDI performance was investigated. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analysis revealed the presence of Si-O bonds on the ACC surface and Raman analysis confirmed the graphitic structure of the ACC was intact after grafting with SiO2 NPs. SiO2 NPs coated ACC electrodes revealed better desalination efficiency and average salt removal rate (ASRR) than pristine ACC. Specifically, ACC electrodes coated with 45 mM silica (SiO2-III) exhibited the highest specific capacitance of 97.4 ± 0.1F/g, average desalination efficiency of 70 % with ASRR of 0.075 ± 0.008 mg/cm2/min using 200 ppm NaCl. Moreover, CDI Ragone’s plot verified the highest desalination rate was achieved with 45 mM SiO2 coated ACC electrodes. Furthermore, different salt concentrations and applied potentials upon desalination performances were also investigated. Moreover, post characterization of used pristine ACC and SiO2-III electrodes exhibited the sign of substantial electrode oxidation for pristine ACC but less on SiO2 NPs coated ACC electrodes. SiO2 NPs decorated ACC electrodes were not only enhanced localized electric field around dielectric coating of SiO2 NPs but also prevented the surface oxidation of the electrodes.

Modified transient plane source method has been applied for thermal conductivity measurements of three water-based nanofluids containing Al2O3, TiO2, and graphene nanoparticles. Experiments were co...

The present study intended to produce biodiesel as an efficient fuel from waste Phoenix dactylifera L. kernel oil in the presence of synthesized efficient heterogeneous metallic oxide catalyst (Mn@MgO-ZrO2). The performance of synthesized metallic oxide catalyst was evaluated based on biodiesel yield and the process has been optimized. The optimum biodiesel yield was 96.4%, when process temperature was 90 degrees C, catalyst loading 3 wt%, methanol to oil ratio 15:1 and reaction duration was 4h. The product biodiesel was characterized in order to evaluate its quality according to ASTM and EN standards. Thus, characterization of biodiesel revealed that it fulfills the standard ranges defined by ASTM and EN: its acid value was 0.11 mg KOH/g, density 881 kg/m(3), viscosity 3.85 mm(2)/s, flash point 142 degrees C and suitable low-temperature properties. It can thus be concluded that synthesized heterogeneous catalyst can be used efficiently for biodiesel production from waste Phoenix dactylifera L. kernel oil which satisfied the international standards defined by ASTM and EN.

Owing to the unique opto-electronic properties, pyrazoline derivatives are considered to be one of the most elegant member in heterocyclic family. In this work we have utilized a pyrazoline dye 3-naphthyl-1-phenyl-5-(4-amino phenyl)-2-pyrazoline (NPAP) for functionalizing graphene oxide (GO) through amide linkage, as the progress of graphene based materials are quicker than other comparable materials. All the employed characterization techniques support the bridging of –NH bond between the two segments. Moreover, the enhanced photophysical properties of the resulting hybrid (GO-NPAP) reflect an efficient charge delocalization, allowing an electronic interaction at the interface of GO and NPAP partners as they are electronically separated. Very simple, economic and an effective reagent for making GO fluorescent, it is expected that the pyrazoline functionalized GO will hold a prominent position in developing high-performance graphene based devices.

This study reports on the fabrication and thermo-physical properties evaluation of ethylene glycol (EG) based heat exchange fluids containing molybdenum disulfide nanoparticles (MoS2 NPs) and micrometer sized particles (MPs). For this purpose, MoS2 NPs and MPs (with average size of 90 nm and 1.2 μm; respectively) were dispersed and stabilized in EG with particle loading of 0.25, 0.5, 1 wt%. To study the real effect of MoS2 NP/MP the use of surfactants was avoided and ultrasonic agitation was used for dispersion and preparation of stable MoS2 NFs/MFs. The objectives were investigation of impact of MoS2 particle size (including NP/MP) and particle loading on thermo-physical properties of EG based MoS2 NFs/MFs including thermal conductivity (TC) and viscosity of NFs/MFs at 20 °C. All suspensions (NFs/MFs) exhibited a higher TC than the EG as base liquid and NFs showed higher TC enhancement values than the MFs. A TC enhancement of 16.4% was observed for NFs containing 1 wt% MoS2 NPs while the maximum increase in viscosity of 9.7% was obtained for the same NF at 20 °C. It indicates this NF system may have some potential to be utilized in heat transfer applications.

Visible light absorption enhanced silver nanoparticles (Ag NPs) decorated zinc oxide nanorods (ZnO NRs) were synthesized using microwave-assisted growth method and utilized as supported catalysts in degradation of pharmaceutical compound. The optimal concentration of silver nitrate precursor and annealing temperature for synthesized ZnO–Ag catalysts were investigated. Different concentrations (5–20 ppm) of paracetamol were used as test contaminant in photocatalytic degradation process. The highest photocatalytic degradation (92%) of 5 ppm paracetamol was achieved for ZnO–Ag in comparison to (54%) degradation for pristine ZnO after 4 h visible light irradiation. The stability of ZnO–Ag catalyst was also investigated. The degradation performance decreased only 2% for ZnO–Ag and 24% for pristine ZnO using 5 ppm paracetamol after four repeated cycles showing high ZnO–Ag stability. Enhanced photocatalytic activity of ZnO–Ag catalyst was due to efficient charge separation as well as visible light absorption and reduced recombination of electron and hole.